1. Field of the Invention
The present invention relates to an impeller puller adapted to facilitate the removal of flexible impellers from the body or housing of various liquid pumps without necessitating that the entire pump be replaced if only the impeller is worn or has become damaged.
2. Description of the Related Art
In various types of liquid pumps, particularly those designed for marine use, elongate flexible impellers are utilized. These impellers vary in their size and dimensions, as well as in the number of blades they include, depending on the particular model or adaptation of the liquid pump. When one of these flexible impellers must be replaced, it is often a highly time consuming and difficult procedure. Commonly, the impellers are removed utilizing a pair of flat head screwdrivers to pry the impeller from the shaft, first separating it from the shaft and then pulling it off of the shaft. In addition to being highly time-consuming, this procedure usually damages the impeller, making it unusable for later reworking, and also can often damage the pump itself. The extent of the difficulty in removing these impellers, particularly in liquid pumps having marine uses, is evident by the fact that often the entire pump itself is replaced rather than dealing with the time and complexity involved in only removing the impeller. Accordingly, a tool adapted specifically to remove these flexible impellers from liquid pumps would be highly beneficial. The impeller puller of the present invention is such a tool.
In the past, there have been patents for various types of puller implements, such as those disclosed in the patents to Frisz, U.S. Pat. No. 1,475,810, Howell, U.S. Pat. No. 1,683,188, Taylor, U.S. Pat. No. 2,484,129, Crane, U.S. Pat. No. 724,818, Bassett, U.S. Pat. No. 1,534,350, and Atkins, U.S. Pat. No. 1,599,738. These devices, which are adapted to remove wheels, gears, and bearings, all utilize standard principals of leverage with their own minor variations making their respective devices suitable for the intended use. For example, the puller implement of Frisz includes a pair of hingedly attached clamp arms, each including an overhanging lip adapted to pass behind the wheel or gear to be pulled, and including an axially disposed screw to help pry the wheel from the shaft. As such, the puller implement of Frisz is primarily adapted to be a wheel puller, the wheel or gear to be pulled generally being substantially narrow and having a somewhat smooth and continuous outer periphery such that the clamp may be disposed about the wheel at any location about its circumference. Similarly, the other referenced patented pullers also include two or three oppositely disposed clamp arms with a single distal lipped portion on each clamp arm so that the clamp arms may pass around the wheel or gear and pull it out. Such devices, however, would not be suitable for removing an impeller from a liquid pump. Principally, impellers are commonly positioned within a housing of the pump which is the same or only a slightly larger diameter than an outer diameter of the impeller defined by its various blades. As a result, the clamp must pass between the blades. This can be a particularly difficult task if the impeller is of the type which includes an odd number of blades. In such impellers, if only two oppositely disposed clamp members were utilized, a proper grip could not be obtained. Further, since the impellers are generally flexible, if only a single lip at the distal end of the clamp members were utilized, uneven pulling would result potentially causing the pulling tool to slip. Accordingly, there is still a need for pulling implement which is adapted specifically for use in removing flexible impellers from liquid pumps.
The device of the specific invention is specifically adapted to meet the needs not addressed by existing implements. It enables full and complete gripping over an elongate surface and is adaptable for facilitated use with impellers of varying dimensions and blade numbers.